Fever -- 8 hot days

In my last post, Fever, I urged parents not to ask a doctor 'What could it be?' The list of possibilities is invariably a long one, and includes some extremely scary diseases that your doctor—like most doctors—has never seen in person. Good physicians always have in mind that if it walks like a duck, quacks like a duck...it's probably a duck. Any sound of hoofbeats is much more likely to be from horses than from a herd of zebras.

So when Matthew's mother called me to say that her 21-month-old has had a fever for about 4 days, I wasn't particularly worried, and told her that. I cared much more about how the child was doing—how sick was he?

Not very, she said. He had a fever pretty much continuously, up to the mid 104's (40°C). He felt lousy at those times, but his mother said that he perked up right away when the Tylenol kicked in. He was eating, keeping up with his fluids, acting like his usual self when the fever was kept down. I didn't need to see him—what was I going to do for him? If he was OK, then I was OK.

On day 5 of the fever, I called the family to check on him. Nothing much was new. Still had high fevers, but nothing in particular was hurting. I told the parents that as a rule-of-thumb, I usually order some basic tests if a child has about 5 days of fever without giving us any clue of what its from.

Most of the time, we don't find anything when we do these tests. And very often, the tests come back normal just as the rash is starting. One of the most interesting and sometimes frustrating common diseases of toddlerhood is Exanthema Subitum, also known as Sixth Disease, also known as Roseola Infantum. It's probably a deep truth about medicine that if you or somebody you know has a disease which has 3 different medical names, it's a good bet that medicine doesn't know much about it. In the 19th century and earlier, the cause of most diseases was completely unknown. So the classification system was based not on the cause of an illness, but on how the physician would witness it progressing. These days, we think of illness as either from a cause of some sort. Back then, there were 6 numbered rashes of childhood. First Disease, for example, is measles. Sixth Disease was a longstanding mystery until 1988 when the viral cause of it was discovered. Luckily, it seems to be the least dangerous of the numbered diseases. What makes it frustrating, and often results in lab tests that turn out to be unnecessary, is the high fever for day after day. Just like Matthew, the kids aren't very sick when we control their fever, which can last for days—usually 3 to 5 days, but I've seen it go a week. Then, mysteriously, the fever goes away and the child gets an awful-looking red rash over their whole body in a matter of hours. The rash doesn't hurt, doesn't itch, and goes away in 1-2 days without a trace and without treatment.

So I knew it was just a matter of patience. The parents, both scientists, were fine with that when I explained the plan. We'd take it day by day, and wait for the rash to appear.

On the morning of day 6, I called for a report. Nothing much was new with Matthew. But in the back of my mind was the fact that this was a boy, with a father is of Asian descent. The longer he went without getting the rash, the more I needed to question if I was right. While I was on the phone, I asked his parents to look at him and tell me if he had any rash of any kind, or if his tongue looked odd or if his eyes were red. I made them describe to me the skin on his hands and fingertips.

About 6pm on day 6, I called and was told that his eyes were a little pink. I drove to their house to look at him. Matthew was watching TV with his older brother, eating a banana. The boys didn't look up when I came in. His eyes were, in fact, a little pink. He wasn't rubbing them, and there wasn't any goopy stuff in the eyes. Everything else looked just as usual. I told the parents that I could wait no longer, and insisted that they take him for a blood test first thing in the morning.

On the evening of day 7, his fever still going, I got the lab results. There wasn't any particular evidence of infection in his blood, but his platelets were about 550, about twice the normal level. That was enough for me. I told them to take him right then, as soon as we got off the phone, to the emergency room at Children's Hospital Oakland. I called the ER and spoke to the doctor in charge so they'd be prepared for him. I told them he had Kawasaki Disease.

I came to the hospital later that night. The treatment was just getting started. We give an intravenous product of filtered, donated human blood called IVIG [Intravenous Immunoglobulin]. It's a liquid packed with all the antibodies and immune cells and chemicals from lots of people, with all the other blood components removed. It's like an immune-system sponge, which vacuums the system of illness-causing agents. We also give them aspirin, the ancient concoction originally from willow bark. It keeps platelets from sticking together (which they are supposed to do in order to help stop bleeding and form blood clots). By day 8, the next day, his platelet count was 750. If it kept going higher, he could be in danger from so many platelets clumping together, making the blood sludge in narrow vessels and potentially causing damage to major organs or a stroke. Matthew was about 26 pounds or so, and we were giving him 4 adult aspirin a day.

Kawasaki disease has yet another mysterious feature. It can cause coronary aneurysms in children. Usually only seen in older adults, these can be serious. They are weaknesses in the walls of the blood vessels that provide the heart muscle with blood. They form bulges in the vessel wall. If the weakened vessel breaks, part of the muscle will not continue working.

This disease is baffling, and reminds me that in past generations there were always those who wondered why they didn't know the cause of some illness even with their incredibly sophisticated 'modern' technology. The disease was only really identified (by Dr. Kawasaki in Japan) in the 1960s. With every technique of current molecular biology, no one has any idea of what causes this.

Because it has occasionally appeared to occur in clusters, it might be something infectious. But if it is, it's very hard to get. It's a rare disease. Maybe some people have a genetic predisposition to be susceptibility to it—it's more common in boys than girls and about 10 times more common in children of Japanese ancestry than in average American children. It's more common in children of other Asian descent than Caucasian children, but less common than in Japanese. Some people think that it's a lot more common than we know. Maybe those old people with aneurysms had unexplained fevers when they were kids, and nobody made anything of it at the time. But it weakened their vessel walls and 60 or 70 years later, they come to the attention of a cardiologist. Maybe adults are getting this disease too, but their symptoms are different. Maybe in adults they're just tired, feel run down, and keep forgetting where they put their keys....

Matthew never got all the symptoms of the disease. Since we don't know what causes it, there's no test for it. By the time I saw him on the evening of day 8, his eyes were very red. Within 12 hours of starting treatment, his fever was gone and he felt fine. Fortunately, the examination of his coronary arteries showed no aneurysms. Who knows how his disease might have progressed if treatment had been delayed by a few days? It's remotely possible he could develop heart-related problems later on, and he will be getting follow-up from the cardiologists. He seems to be fine for now, and he takes a chewable aspirin every day.

Don't ask your kid's doctor what it could be. Just try to find a doctor who knows that there are zebras out there, and who might recognize one at a distance.

Copyright 2009 Wolffe Nadoolman